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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="vue.js"></script>

</head>

<body>
    <div id="app">
        <input type="text" autofocus @keyup="handleKeyup" />
        <p v-show="isCapsLock">已经开启大写</p>
    </div>
    <script>
        new Vue({
            el: "#app",
            data: {
                isCapsLock: false
            },
            methods: {
                handleKeyup(e) {
                    if (e.key) this.isCapsLock = !this.isCapsLock
                },
            }

        })
    </script>
</body>

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